organizations, including the fbi and the boston police department gave the latest on their investigations. >> our mission is clear, to bring to justice those responsible for the marathon bombing. the american public wants answers, the citizens of the city of boston and the commonwealth of massachusetts want and deserve answers. this remains a very active investigation, our ongoing investigation in various locations throughout the area goes on. however, there are no known additional threats. i'm not going to say who is, who it might or might not be in custody right now. >> we are in the process of securing and processing the most complex crime scene that we've dealt with in the history of our department. >> here is what we know at this hour there were two confirmed explosive devices containing ball bearings, contrary to earlier reports, there were no other unexploded devices at the scene. nbc news is also reporting that officials are studying surveillance video and have focused on one piece of tape showing an unidentified person carrying two back pacs.

too early to know if it may be related to the blasts. overnight, law enforcement officials searched an apartment in northern boston massachusetts, police could be seen removing things from the residence, but nothing of interest was found. the home belonged to a 20-year-old man here on a student visa who sustained burns and was seen running from the blast. a senior law enforcement cautioned nbc news that the man is not a suspect and the interest in him is fading. internet chatter has been ruled out. one terrorist group, the pakistani taliban, behind the failed times square bombing of 2010 have told police it is not responsible. and police are on the lookout for a man seen leaving the scene in a dark piece of clothing and a rental truck scene attempting to entry the area near the finish line. msnbc contributor joy reid and

joining us from washington is nbc news justice department correspondent pete williams. pete, i'd like to go to you first, given what the president just said coming out and saying it is an act of terror does not come as much of a surprise, given the contours of this. but still something worth remarking on in terms of how the white house is handling this event. >> perhaps so. but this is a case of you know, do as i say, not as i do. or perhaps actions speak louder than words, is what i meant. the very fact that it was announced last night that the fbi was taking the lead in this investigation answered the question. because the fbi has jurisdiction in a case like this only if it's considered an act of terrorism. we crossed that bridge last night. with the words were used or not. in terms of the investigation, let's just clear up a couple of points that were confusing overnight. just two devices, there was a suggestion there were others because so many packages had to be destroyed. there was mixed information about whether any of them campaigned explosives, they did

not. sports are starting to learn more about the kproe significance of the bomb. how it was constructed. how, how the detonators worked. they're beginning to understand how these things were constructed. that will be a very important piece of information as they try to pursue where did the parts come from. that's one avenue in this investigation. there was a search overnight, you may have heard of apartment of a student who is here, 20 years old on a visa. studying at an english language university in the boston area. nothing of value was found in that search. he's been cooperative. people in the scene thought he was acting suspiciously. he's been extensively questioned. he denies having anything to do with this. although obviously they'll continue to look into his background, i would say interest in him is waning rapidly. and they've been quite clear that they have no suspects in custody. so the investigation now will pursue along several tracks. one is the pieces themselves, what is recovered from the scene.

bits of shrapnel that are recovered from the victims. all of those things will be, to the extent that they can reassembled to try to understand how this was built. secondly, as the authorities said today this had to be one of the most photographed areas in the country yesterday. because of the marathon. they're asking for lots of pictures, lots of videos, so that they can try to match them all up and get some sense of frame by frame, what was happening in the minutes before these devices were placed and detonated. they're starting to get a lot of pictures and some of them, i'm told, are considered valuable. they're also looking at surveillance video from nearby stores. the other kind of video that exists. that is a process that's still going on. there's a lot of it. and so that may be an avenue, too. in terms of witness statements, they're questioning people who were there, who were injured in the hospitals. they're trying to talk to as many people as they can to see if someone saw something or someone saw something being set down at the places where these

explosions went off. and then there are also going back and looking down at the intelligence streams that led up to this. was there any claim of credit early on, were people seeming to know about this before it happened? so far that has not seemed to lead anywhere. but that's a process that will take a while. >> pete, to that point of all the footage that is coming in, whether they are still photographs or video, there must be a huge amount of data, a lot for the fbi to sift through. do you get a sense that there is some sort of orderly process in which they are taking this material in? >> oh yes, it will all be cataloged in terms of who it came from. how to get in touch with those people. talk to any certain people. but, yes, they're experienced in how to do this. and, how do match this all up. how to store it frame by frame. so that for example, you know that at 2:45:32.1, here are all

the still videos and footage. that's the goal to get that kind of frame-by-frame thing to go through the minutes, that will take a while to build. >> pete before we come to our panel here in new york, ha do you make of the fact that the pakistani taliban is going so far out there to say this is not our work, we have nothing to do with this event? >> i haven't slightest idea. i don't think much stock is put in statements, we didn't do it, we did do it at this point until they get better evidence to say where the investigation is going. >> pete williams, hang with us, we'll have more questions for you within the hour. thank you for your time for the molt. i want to open it up to the panel in new york. katrina, we talk about just in the short time that i've been at this desk, with this show, there have been a number of disastrous incidents in terms of violence, massacres, bombings. >> boston isn't, they're all sort of different in their way.

it forces upon us this sort ever collective fear, but also, a sense of community. which of course would be the silver lining here. and we're going to talk to some firsthand i witnesses laeye witn the hour. one thing that's striking in the moments of duress and tragedy is how the country unites together, whether it's rushing to the aid of those wounded in the smoke and fire. and as the president said, it shows us who we are as americans. >> it does. i think you know we know we don't want to engage in baseless speculation. what we know we need to do is grieve. we need to pay respect to the heroic first responders, to the kindness of boston, to the community, and the community we've seen come together in the aftermath of whether it was 9/11, or newtown. or in boston. the whole issue of whether to call it terrorism it seems to me what's so important is just who did it, how it was done. why. and not the name at this point. but it is clear that terrorism

terrorists want to terrorize us. want us to concede to fear. my hope is that the community spirit, the resilience of the american people, which the president spoke so well to is what comes out of this. not the overreaction to fear, which i think we have seen for sure in the wake of 9/11 when this country overreacted and allowed unamerican things and the shredding of principles that make this country great. allowed the indefinite detention of people or allowed the warrantless wire-tapping or allowed a report on the front pages of newspapers today, the news goes on amidst the tragedy of indisputable evidence by a bipartisan commission that america tortured. so i think community, resilience, kindness, those are the great qualities that can make this country strong again. >> and we will be asking ourselves a lot of questions as we figure out who the suspects were, as law enforcement officials figure out who is a leading suspect.

what the motivation might have been. let's bring in msnbc terrorism expert and former director of the national counterterrorism center, michael whiting there are so many questions and one of the sort of meta questions i have is are you surprised that so very little is known about this 21 hours later? certainly it is a very, a lot happened, the scene itself we hear was chaotic. pandemonium ensued. at the same time, the president came out this morning i think a lot of folks were expecting him to deliver some new piece of information. there was none from the white house. >> i'm not that surprised, alex. in fact what we do know is some of the things that were initially reported and in fact are wrong. and that's really step one. just knowing how many devices went off. where they were located. i mean that seems obvious, but as we saw from the videotape, the pandemonium, it's hard to get all that clear. so that's step one. from there, it is such a painstaking process of looking at all the possibilities, piecing everything together and

not running down a rabbit hole too quickly. a, it was on april 15th, it must be about taxes ora, it looks like sunni extremist terrorism. keeping the options open, collecting the data and going through it methodically. you always hope the early break, but it absolutely does not always come. >> on some level, i think you're right. acting with an abundance of caution, no the jumping to conclusions is laudable. but it does say something that we don't really know if this is a domestic act or an international act. i don't think it's necessarily, it's definitely not a good thing, that it could be either way. the notion that this could be a home-grown terrorist, a lone wolf terrorist it prompts an examination of the hate and extremist groups in this country. we know about terrorist groups outside the country. it's a testament to how unsettled this world is, how dangerous it is, the number of

groups that have mushroomed inside and outside our borders that want to do harm to american innocent citizens, innocents all over the world. >> i agree. the fact that you have more than one group of suspects, that's not good. that's certainly true and it's also obviously not good that we didn't get or at least we didn't recognize yet, any intelligence warnings about this specific plot. on that latter point, that really is the nature of terrorism, we're going to be surprised sometimes and we have lots of things in place, defensive measures, offensive measures to try to minimize the likelihood of attack. your point that there are multiple groups that might pursue tactics like this. that's certainly a bad sign. i would say i don't think we have short memories in this country. we shouldn't say that this time is really unique in american history. whether you go back to the anarchist in the early 20th century or palestinian terrorism

in the 1970s, we have had these periods before. this is probably a more deadly period. but you know, in all these cases, we really have recored and the country moves forward. >> joy, we talk about as michael said. this is not without precedent. there was of course, the 1993 world trade center bombing where six people died. the oklahoma bombing, 168 people killed. the olympics bombing, two killed and the fort hood shooting where 13 people were killed. the president for his part seems to be taking this dealing with this one slightly differently than he did the underwear bomber earlier in his tenure, he's come out early. he is apparently going to come out often. he said at the end of the statement, he will be getting continued updates from law enforcement officials, i imagine this is not the last type we will see the president. he is with the american public on this one in a way that perhaps he hasn't been as sort of present and on your television screen the way that he is now. i think one of the lessons in

the learning curve for president obama has been the importance of communication. a lot of different issues that are important to him to his presidency. you do have to have the presence. the whole purpose of these kinds of acts of terrorism is to destabilize you, make you afraid to get on the subway. to make you afraid to go into a mall. to make you afraid, no matter where you are, even if you're far from the actual incident. having sort of one person that is constantly communicating with you is very important. i mean we learned after 9/11 that when george w. bush didn't do it, rudy giuliani stepped in. so the whole country was waiting for him to come on the television for those first couple of weeks, because you didn't see the president. and i think president obama has learned the lesson that you do have to speak early, speak often, speak confidently and i'm glad he's kind of cautious, to be honest with you. i know sometimes there's a fetish in american for sort of bellicose language. it makes us feel we're going to get whoever did it but when you don't know who did it, there's not a lot of bellicose language that's useful. it's more useful to find out who did it, to be methodical, find out what's happening. and i think the mashed obama is

one of the reason he is got elected, he's a stable, measured presence. it's important that he do that, but also be present. >> michael before we let you go, there's demand for answers, a lot of pressure on naming a suspect. but in the end, i mean this could take a considerable amount of time. you think about the anthrax attack, post 9/11. the answers around that remain sort of hazy to this day. as an expert had has dealt with these issues before, i'm sure you would caution us that the solutions may not be forthcoming in any sort of short timeframe. >> i would be and i think that messaging has been coming out loud and clear from the white house and the task force and the mayor and governor of massachusetts, i think that's very good. the other thing i'm very happy hasn't happened yet and i hope it doesn't, is that we don't engage in political fingerpointing about why this happened. we've got to grieve for the victims, take care, make sure we have things secure. figure out who did this. and then there will be a time to reflect on this. and there will be a time to know

if we missed something. but i'm very, rerelieved to see right now we're given the counterterrorism national security professionals room to do their job. >> michael leiter thank you for your time and expertise. despite the many news conferences and updates, there's more questions than answers about what happened yesterday. we'll go live to boston and talk with one of the eye witnesses to the bombings, coming up next on "now." welcome to the new new york state, where cutting taxes for families and businesses is our business. we've reduced taxes and lowered costs to save businesses more than two billion dollars to grow jobs, cut middle class income taxes to the lowest rate in sixty years, and we're creating tax free zones for business startups.

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patriots day is a state holiday in massachusetts, in boston it's an annual celebration. schools and businesses closed, the red sox played 11:00 a.m. and runners in the nation's oldest marathon take to the city streets. it is a tradition that dates back to the start of the revolutionary war at lexington and concord. the first boston marathon was held back in 1897. this year, tradition turned into terror. just before the finish line of the marathon, two bombs exploded 15 seconds apart. here is the video captured by the "boston globe's" steve silva.

>> the blast killed at least three people and injured more than 150. 8-year-old martin richard is among those who were killed. he was watching the race with his mother, father and sister. >> we are reporting two explosions here. we have police, people with serious injuries. >> there was just families all around us, with kids, yelling and screaming. and we just wanted to try to get away as quick as possible. >> took off down the street. and the police were all running towards the incident and we were running away. >> it was pandemonium. everybody started running and screaming and we saw people bleeding and you know, it was unlike anything i had ever seen before. >> the guy next to me and his wife, she lost her limb and we help him and help her get in an ambulance. it was unspeakable images. that nobody should ever see.

and it's contradictory to the spirit of america. >> while law enforcement says no one is in custody. investigators spoke last night to a 20-year-old man on a student visa seen running from the blast. this morning officials would not comment on specific persons of interest. but said the investigation is far-reaching. >> this will be a worldwide investigation. we will take us where the evidence and leads take us, we will go to the ends of the earth to identify the subject or subjects who are responsible for this despicable crime. >> on a day that has been traditionally set aside to honor the runners, boston is honoring the victims. >> the day after the marathon, as you well recall, both papers, the "globe" and the "herald" run the names of all those who finish the marathon. and the sadness of today, the legacy of yesterday, in part is going to be that in today's papers, we are listing the names of those dead and wounded.

>> emerging today are also profiles in courage. which president obama noted in the last hour. the world saw yesterday the aftermath of the explosions were stories of heroism and kindness and generosity and love. exhausted runners who kept running to the nearest hospital to give blood and those who stayed to tend to the wounded. some tearing off their own clothes to make tourniquets. >> mile 26, the site of the blasts had been dedicated to the 26 victims of the newtown shooting. the final mile will now be remembered for its own tragedy and patriots day will now care are i new meaning. joining us from boston, the host of msnbc's "jansing and company" chris jansing. thanks for joining us. >> many of the people from newtown actually were here because of that dedication of the last mile. some of the family members, some residents were either running or cheering on. none of them was hurt. but we do now know and got confirmation this morning that

176 people were taken to hospital. three of them died. you mentioned martin richards, just eight years old and two of those seriously wounded. and there are 17 in critical condition, but two of them are his mother, who had brain surgery and his sister who lost one leg. all of them were there to watch martin's dad run in this marathon. you mentioned two explosions, confirmation this morning from investigators there were two blasts. they were a few hundred feet apart. about 15 seconds apart. you can just imagine the scene at that finish line. there are 23,000 people who are running in this marathon, about two-thirds of them had finished by that time. there's bane lot of talk about the people who had yet to finish. they were the folks whose, you know, families were there, really cheering them on. people who you know, maybe weren't the youngest. weren't expected you know to finish among the top. but many of them who had made a personal commitment, that they would run. and in what is arguably the most

heralded footrace that there is. this morning a few blocks behind me, investigators are working. they have reduced the active crime scene, from 15 to 12 blocks, they can take down the tape of course, alex. but restoring the sense of security and that sense of calm and certainly the sense of celebration that is typical on marathon day here in boston will take much longer. >> restoring that sense of security will take some time. chris jansing, live from boston, thanks for the update. >> senior sports reporter for the "boston globe," steve silva he captured video of the blast as it happened. thanks for joining us, give us a sense of what it was like. you ran toward the scene of the crime as it were. just incredibly chaotic and certainly very dangerous, give us a sense of what that experience was like for you. >> it was very calm and usual right before the explosion. i was just out there videotaping

the runners coming across the finish line as i usually do to put a compilation video together for the paper and for the website. for the morning. and just trying to find interesting characters doing cartwheels or push-ups at the finish line. when all of a sudden at 2:50, big loud thud, boom, flash of smoke went up. i thought it was a cannon salute to someone, but that didn't seem to make too much sense. didn't think i was rushing towards and explosion. just had to go over and check out what was going on. as we were getting a grasp of that situation, 12 seconds later the other bomb went off, up the street on fairfield and boyleston. and when i got closer to the railing where the first explosion went off and saw the sidewalk and the pool of blood and bodies lying around and a man with his leg severed at the knee, you knew this was a war zone situation. >> what's notable on the tape you're quick on your diagnosis,

that this is an attack, given how chaotic the situation is that's a testament to where the national psyche is in terms of events like this happening and immediately, our minds go to terrorism. which seems like it was the case yesterday in boston for you. >> it wasn't scripted, i was just shooting, i wasn't planning on doing a voiceover. but i thought i needed to capture this. i wasn't going to pan over the sidewalk. i looked, i kept the camera up. and i made the determination. some type of an attack for sure. it wasn't an accident. it wasn't like anything we had ever seen before. >> steve, i want to bring in some of our panelists here in new york. and katrina, you and i were speaking a couple of minutes ago. about the fabric that weaves american society together and oftentimes moments like this test the strength of that fabric and actually bind us closer together. i read an editorial from the

"washington post" where they write in the early moments of the blast there were indications of the nation's maturity for better or worse in dealing with such shocks. runners and onlookers seemed to respond without panic. local police began cooperating seamlessly with state police and the fbi and other federal authorities. emergency crews responded with professionalism. officials and reporters, meanwhile, were careful not to get ahead of the confirmed news. we talk about 9/11 and the legacy of that. but really legacy of all of these tragedies may be the resilience of the american people. >> i do think that since 9/11 and your guest before i think was right to remind us that we shouldn't be the united states of amnesia. that this country has lived with acts of violence without its history. and other countries have lived with acts ever violence and have not let those acts undermine the values and fabric of a society and what's great about it. i want to call out because we just had steve silva on. we're reporters and often when we hear about these tragedies, i

remember 9/11, you have to put aside your personal feelings and go to work in a humane sense and a clear-eyed way. how to explain. and i think what happened yesterday in boston, is happening today, is "the boston globe," the paper under siege in different ways, performed a great community service for community and grief, brought together, didn't speculate baselessly, brought people information they needed. and a more mature social media worked to bring information to people. and you didn't have, you had after mcveigh, the speculation about muslim bombers or after 9/11, which of course was a wrenching traumatic framing experience, which some of the victims spoke of remembering as this happened. or the 1996 bombing at the olympics, never forget that. this was a sporting event. but i do think that -- though a great city had its humanity subverted and ripped apart at one of these great rituals we

talk about, that people emerge from this coming together and i hope that remains the case. because this country needs politics, but not the politization and the senseless reversion to fear-mongering that has defined that politics. >> steve, katrina makes a great point about news-gathering and the "globe" in this particular moment, the reporting that you and your colleagues are doing, how incredibly necessary it's been. and i also the maturation of the news cycle to some degree. the caution is actually being heeded. that you know, there's not been a lot of circumspect theories floated out there. to you and the "boston globe" staff, in boston in particular, patriots day, e.j. dioe dionne has a great op-ed piece.

it is traditionally such a big day of coming together for boston residents. the impact of this, i don't think you can underestimate for those of us who don't live in the city. if you could give us a sense of that. >> anyone you've talked to, anyone who has moved here, say this is the day to be in boston, our greatest day. it's patriots day. we've got the 11:00 red sox game. you've got the boston marathon. where you not only have the elite runners of the world running but you have everyone knows somebody running in the boston marathon one way or another. typically through a charity event, they're out there supporting someone. so everyone is tied into this event. most everyones had the day off. all the bars are open for big parties, it's a day to celebrate a launch pad into the spring. and that day is forever changed, it will never be the same. the boston marathon will never be the same. going to a big live events this summer is going to be the same in boston. it's gone from great tradition to a senseless tragedy in the blink of an eye. >> the "boston globe's" steve

silva. thank you for your reporting and thank you for sharing your experience with us. >> you're welcome. coming up, police say 170 people came to boston-area hospitals in the aftermath of the bombings and many are still in critical condition. a live update on the victims, that's next. we've all had those moments. when you lost the thing you can't believe you lost.

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hospitals. earlier today, one of the doctors at mass general briefed the press at some of the injuries they were seeing. >> nails. yeah. or sharp objects. i can't say what they are with certainty, but that's how they look like. >> do you know how many? >> they are numerous, numerous. they're people who have 10, 20, 30, 40 of them in their body this bomb obviously was placed probably low on the ground. and therefore, large extremity injuries are to be expected. almost all of them had such severe trauma in their lower extremity, it was beyond salvation, i would consider almost automatic amputees who just completed what the bomb had done. >> doctors held a press conference at tufts university where nbc's kerry sanders joins us now, what's the latest from your end? >> well i think we can tell you about one particular story that sort of describes the ordeal

that so many patients are having to deal with. these are victims. let me tell you about lee anne and her husband, nick yahne. they were here to participate in cheering on a friend, they were right there at the finish line. when the bomb exploded, that first one, it sent shrapnel in a 360 degrees, and one of the ball bearings came out and hit lee anne in the left leg. it went through her leg, broke her femur and caused the open wound to begin bleeding out. right as she was laying there on the ground. her husband, nick, was nearby. but the concussion of the explosion caused him to momentarily go deaf. so he said it was sort of silent as he was looking around for his wife. as she was laying there, they were eventually -- >> that was kerry sanders live in boston. we're just getting in some developing news right now. an official of wisconsin's carroll university tells nbc news there is an ongoing

lockdown situation at the school. there is a report of a man with a firearm in the university is keeping students indoors. police do not have any information available at this time. we will of course continue to monitor it and give you the updates when we get them. coming up, beyond the how manien toll, the attack in boston, we'll have an emotional impact on the people of the city and the country. we'll discuss tragedy's lasting events on american sipsyche, ne. with the spark cash card from capital one... boris earns unlimited rewards for his small business. can i get the smith contract, please? thank you. that's three new paper shredders. [ boris ] put 'em on my spark card. [ garth ] boris' small business earns 2% cash back on every purchase every day. great businesses deserve unlimited rewards. read back the chicken's testimony, please. "buk, buk, bukka!"

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whether it's mass shootings or these random terrifying bombs. >> that was tom brokaw, speaking about the emotional impact of the tragedy like yesterday's bombing at the boston marathon. president obama spoke in the last hour about the response in and around boston over the past day. >> the medical students who hurried to help saying when we heard, we all came in. the priests who opened their churches and ministered to the hurt and the fearful. and the good people of boston, who opened their homes to the victims of this attack, and those shaken by it. so if you want to know who we are, what america is, how we respond to evil, that's it. selflessly, compassionately, unafraid. >> that sentiment is felt across the country, cities and towns including this one here -- last night the brooklyn academy of music displayed the message, darkness cannot drive out darkness, only light can do that. new york loves boston.

joining us is the chairman of psychiatry at the columbia university medical school, dr. jeffrey lieberman, dr. lieberman, thanks for joining us. >> sure, my pleasure. >> we're talking about the impacts of events like this on the american psyche. it would seem to be that the collectivism, an idea that we need to strengthen the ties that bind as it were. would be one of the first stages of dealing with grief. i mean how accurate do you think that is? >> well, individual differences different points of view dissipate in response do the tragedies or large events. and something like what happened in boston was a large event which puts everything in perspective. nobody who was in boston that day, yesterday, and nobody particularly who was in proximity to the marathon will ever forget what happened. it will be em blazeden into their mind, much like many historical tragedies are in the american consciousness. whether it's pearl harbor or the day president kennedy was

assassinated or challenger exploded or 9/11. this will have the same magnitude for bostonians. a double tragedy, an emotional trauma to be put unexpectedly in a life-threatening situation in a situation where you would never expect that to occur. but then in addition, it occurred on a day that is such a celebration in the hometown of the people that were there. so in addition to being an emotional trauma, it was a violation, a violation of the sanctity of the spirit of the day. it really penetrates to the core of people's sense of security. >> i think one of the things that remains a question mark is how people will deal with the inevitable anger that arises from something like an act of terrorism. after 9/11, joy, we saw obviously there was a huge response both in terms of the starting of the wars in iraq and afghanistan and some fraying in

terms of the american sort of fabric. the question is how do we make sure that doesn't happen again, once there is a suspect, once we have greater information of who did this? >> that's wung of the things that i've been really relieved about, that there hasn't been an immediate jumping to conclusions. all sorts of things can happen when you jump to conclusions, you need to get back to the people you think who did it racial profiling, the reaction against another. because we don't know who did this. i think that's one of the good things. the other thing that's been interest